This invention relates to load pull testing of microwave power transistors using automatic microwave tuners in order to synthesize reflection factors (or impedances) at the input and output of said transistors.
A popular method for testing and characterizing microwave components (transistors) for high power operation is “load pull” and “source pull”. Load pull or source pull are measurement techniques employing microwave tuners and other microwave test equipment, such as signal sources, power meters and directional couplers. The microwave tuners in particular are used in order to manipulate the microwave impedance conditions under which the Device under Test (DUT, or transistor) is tested (FIG. 1a).
Many users require impedance tuners to cover a wide frequency range. In laboratory environment, in particular, test setups are expensive and applications may vary from low megahertz to high gigahertz frequencies. A tuner unit being able to operate over such wide frequency ranges would then be required, but has not been introduced, yet.